bellringer 10/07 what do you think this cartoon is about? what do you think is happening?
Post on 26-Dec-2015
229 Views
Preview:
TRANSCRIPT
Bellringer 10/07
• What do you think this cartoon is about?
• What do you think is happening?
The Story
of Cells
What are we made of?
What are cells?The Building Blocks of Life
The cell is the smallest structural unit capable of performing life
functions.
Cell Trivia
• The average human being is composed of around 100 Trillion individual cells!!!
• It would take as many as 50 cells to cover the area of a dot on the letter “i”
Discovery of Cells
1665- English Scientist, Robert Hooke, discovered cells while looking at a thin slice of cork (bark of tree)– He described the cells as tiny boxes or a honeycomb– He thought that cells only existed in plants and fungi
The Microscope!
1673- Anton von Leuwenhoek, invented the microscope and observed pond scum and discovered single celled organisms
•He called them “animalcules”He called them “animalcules”•He also observed blood cells from fish, birds, frogs, dogs, He also observed blood cells from fish, birds, frogs, dogs, and humansand humans•Therefore, it was known that cells are found in animals as Therefore, it was known that cells are found in animals as well as plantswell as plants
More history…
• 1838- German Botanist, Matthias Schleiden, concluded that all plant parts are made of cells
• 1839- German physiologist, Theodor Schwann, who was a close friend of Schleiden, stated that all animal tissues are composed of cells.
• 1858- Rudolf Virchow, German physician, after extensive study of cellular pathology, concluded that cells must start from preexisting cells (BIOGENESIS)
Where does life come from?
• Old Theory - Spontaneous Generation
• Life spontaneously happens:
Life comes from non-life
• Examples: – Mice from cloth sacks and grains.– Maggots from rotting meat.
REALLY?
Where does life come from?• Much doubt existed around Spontaneous Generation• Conclusively disproved by Louis Pasteur
+
=?
Ummm, I don’t think
so!!!
Where does life come from?• 1858- Rudolf Virchow, German physician, after extensive
study of cellular pathology, concluded that cells must arise from preexisting cells.
Biogenesis – Life can only be formed from existing life.
The Compound Light Microscope
• Lenses• Light• We’ll be
using it!!!• Up to
x1500
Our Microscope…
The Electron Microscope• Biggest magnification (X 2,000,000)• 2 types (SEM and TEM)
The Cell Theory
1. All organisms are composed of one or more cells.
2. The Cell is the smallest working unit of living things.
3. All cells come from pre-existing cells through cell division.
Basic Parts of a Cell
All cells have certain structures in common.
1. Nucleus- contains genetic material (DNA)2. Cytoplasm – a semifluid matrix (like the
eggwhite of an egg)3. Plasma membrane – a phospholipid
bilayer- like the shell of an egg4. Organelles- specialized structures in the
cytoplasm
1st Look at THE CELL!!!
Examples of Cells
Amoeba
Plants
Red Blood Cell
Nerve Cell
Bacteria
Two Types of Cells
•Prokaryotic •Eukeryotic
REMEMBER US
Prokaryotic Cells
• Do not have a membrane-bound nucleus or organelles
• Few internal structures (organelles)
• Usually one-celled organisms like bacterias
Eukaryotic Cells• They do contain a membrane-bound nucleus and organelles and are more complex.
• May be unicellular or multicellular
Plant Animal
“Typical” Animal Cell
“Typical” Plant Cell
BELLRINGER 10/151. WHAT ORGANELLE
PRODUCES ENERGY IN THE CELL?
2. WHAT ORGANELLE CONTAINS CHROLOPHYL?
3. WHAT ORGANELLE PACKAGES SUBSTANCES IN THE CELL?
4. WHAT ORGANELLE CONTAINS RIBOSOMES?
Organelles
Surrounding the Cell
Cell Membrane (Animal and Plant)
• Outer membrane boundary of cell that controls movement in and out of the cell
• Double layer with pores (holes)
Cell Wall (Plant)• Most commonly found in plant cells & bacteria• Supports & protects cells• Rigid (tough), outside the cell membrane• Contains cellulose
Inside the Cell
Nucleus (Plant and Animal) • Directs cell
activities- the brain of the cell
• Separated from cytoplasm by nuclear membrane (envelope)
• Contains chromatin (DNA)
Endoplasmic Reticulum (Animal and Plant)
• Highly folded membrane that produces, transports proteins
• Smooth type: lacks ribosomes
• Rough type: ribosomes embedded in surface
Ribosomes (Plant and Animal)
• Each cell contains thousands
• Make proteins• Found on
ribosomes, nuclear envelope & floating throughout the cell
Mitochondria (Plant and Animal)
• Produces energy (ATP) through chemical reactions
• Highly folded membranes
• Has its own DNA
Golgi Apparatus (Plant and Animal)
• Protein 'packaging plant'
• Move materials within the cell
• Move materials out of the cell
• Flat tube system
Lysosomes (Animal)• Digestive factory and breaks down waste (proteins, fats,
and carbohydrates) with enzymes• Transports undigested material to cell membrane for
removal• Cell breaks down if lysosome explodes
Vacuoles (Plant and Animal)
• Membrane-bound sacs for storage, digestion, and waste removal
• Contains water • Help plants maintain
shape• Many small in
animal, 1 big one in plant cells
Chloroplast (Plant)
• Found in plant cells• Contains chlorophyll
(gives color green to plants)
• Where photosynthesis takes place (plants make own food from light energy)
Centrioles (Animal)
• Only in animal cells • Play role in cell
division (mitosis)• Organize
microtubules in bundles
• Make up the centrosome (near the nucleus)
Cillia and Flagella (Animal and Prokaryotes)
• Mostly in unicellular organisms (animal only) and bacteria • For movement and fluid transport• Cilia = many little hairs on the cell body• Flagella = few/one tail(s)
Cytoskeleton (Plant and Animal)
• Network of rods (microtubule) and filaments (microfilaments)
• Gives cell support, structure and shape• Involved in cell division (mitosis) and transport
The BIG Picture again!QUIZ TIME!!!!
USE THE FOLLOWING SLIDES and your NOTES to answer the following…
1. Identify the cells that follow. 2. Identify 3 organelles that exist in BOTH plant and animal
cells.3. Identify 2 organelles that exist ONLY in an animal cell.4. Identify 2 organelles that exist ONLY in a plant cell.5. What is the difference between cilia and flagella?6. Identify 2 differences between prokaryotes and eukaryotes.
QUIZ TIME
Let’s compare…
top related